Humanity’s Existence Depends on Love Gambling with Another World’s Princess

Humanity’s Existence Depends on Love Gambling with Another World’s Princess
The Great Demon Lord’s daughter, Lumis, joins an all-girls boarding school to experience romantic love, and joins the class of the only male teacher, Kazuki. One day, Kazuki overhears that the Great Demon Lord will destroy the earth if he makes his daughter cry…!? The ultimate heart-throbbing rom-com commences!